Brake



Patented Aug. 25, 1942 UNITED STATE s PATENT OFFICE BRAKE Application May 13, 1940, Serial No. 334,728

2 Claims. (Cl. 18S- 78) s lThis invention relates to brakes, and is illustrated as embodied in an internal expanding brake v ior an automobile.

An object of the invention is to position the shoes by engagement of the edges of the rims with projections 'or ledges on the backing plate.

and to prevent the rubbing movement of the shoes on these projections from causing undesir.

able noise. This is accoinplishedby slitting the shoe rims, as described below, opposite the projections on the backing plate.

The above and other objects and features of the invention will be apparent from the following description of the brake shown in the accompanying drawing. inwhich:

Figure 1 is a section through the brake, just inside the head of the brake drum, and showing the shoes in side elevation:

Figures 2 and 3 are partial sections on the lines 2-2 and Hoil'lguxeh'and v Figure 4 is a partial section through one shoe rim.. illustrating the slitting of the rim.

The brake illustratedincludes a drum Il. at

the shoes rub against projections or ledges I4 when the brake is applied or released. To prevent this causing a `squeaky noise, on account of this vmetal-to-metal rubbing contact, the rims oi the shoes are formed .with slits 38 near their edges, and extending lengthwise of the shoes, opposite these projections il. Figure 3 shows this arrangement.' the brake lining Il being broken away in this ligure to show theiace o! the shoe rim. Siits may be provided at both sides of the rim,sothatthe shoes and ilwillbeinterchangeable.

These slits may be formed, without remov-` ing metal, by shearing the metal oi the rim and l5 'bending down tongues extending between holes the open side of which is a support such as a backing plate i; formed with projections or Il for positioning brake shoes Ii and il.

shoes are connected by an adjustable strut 20, and are provided with suitable steady rests 22 and return springs 24. The shoes are 4applied alternatively by a wheel cylinder type hydraulicr vapplying device 2l, or by a mechanical applying device such as a cable 28 actuating a lever Il and strut l2. One shoe or the other anchors. when the brake is applied. on an anchor pin 84.

Itwlll be noted that the'edges ot the rims of 4l (Figure 3), in the manner shown in dotted lines in Figure 4, and then pressing these tongues back flush with the rim again.

While one particular brake has been described. it is not our intention to limit the scope of the invention to that particular: brake, or otherwise than by the terms of the appended claims. e

We claim:

1. A brake ,having a* backing plate provided ledges 2s with positioning projections, and brake shoes I'hese havingrims engageable at their edges with said projections, said rims having slits extending lengthwise o! the shoes near the edges o! the rim opposite said projections.

2. A brake having a backing plate provided with positioning projections, and brake shoes engueable at their edges with said projections, said brake shoes having slits opposite said projections.

' DONALD J. AYER'S.

ROBERT Il.' STRIL'BTINGER.s I 

